title: Nascent lobar microbleeds and stroke recurrences.
abstract: BACKGROUND
  Lobar microbleeds (MBs) are occasionally visible on gradient-echo T2*-weighted (T2*-w) magnetic resonance imagings (MRIs) in patients with deep intracerebral hemorrhages (ICHs). This study investigated the contribution of nascent lobar MBs to occurrences of deep ICHs.
  
  
  METHODS
  We prospectively analyzed nascent lobar MBs in patients admitted to our hospital who were treated with index strokes between April 2004 and November 2009. Numbers of nascent lobar MBs were counted on T2*-w MRI scans around 1 year after index strokes and compared with previous MRIs on admission. Deep ICH occurrence-free rate curves were generated by the Kaplan-Meier method using the log-rank test. The odds ratio (OR) for deep ICH occurrence was derived from a multivariate logistic regression model using nascent lobar MBs and risk factors.
  
  
  RESULTS
  We investigated MRIs (interscan interval: 14.6 ± 5.9 months) of 508 patients (207 women, 68.9 ± 11.5 years), with a follow-up period of 44.1 ± 15.4 months. Repeated T2*-w MRIs demonstrated 157 nascent lobar MBs in 62 of 508 patients. The occurrence rate of deep ICHs (1.9% per year) was significantly higher in patients with nascent lobar MBs than in those without (.5% per year, P = .012). Multivariate analyses revealed that the rate of nascent lobar MBs was significantly elevated in patients with deep ICH-type stroke recurrences (OR: 3.85, P = .020), adjusted by the presence of hypertension, diabetes mellitus, use of antithrombotic drugs, severity of white matter lesions, age, and gender.
  
  
  CONCLUSIONS
  Though a cohort study limited the power of analyses, our findings suggested that lobar MBs might be associated with deep ICH.
authors.affiliation: Department of Neurosurgery, Kushiro City General Hospital, 1-12 Shunkodai, Kushiro, Hokkaido 085-0822, Japan. Electronic address: timaizum@d9.dion.ne.jp.
authors.forename: Toshio
authors.initials: T
authors.lastname: Imaizumi
authors.affiliation: Department of Neurosurgery, Kushiro City General Hospital, 1-12 Shunkodai, Kushiro, Hokkaido 085-0822, Japan.
authors.forename: Shigeru
authors.initials: S
authors.lastname: Inamura
authors.affiliation: Department of Neurosurgery, Kushiro City General Hospital, 1-12 Shunkodai, Kushiro, Hokkaido 085-0822, Japan.
authors.forename: Ikuhide
authors.initials: I
authors.lastname: Kohama
authors.affiliation: Department of Neurosurgery, Kushiro City General Hospital, 1-12 Shunkodai, Kushiro, Hokkaido 085-0822, Japan.
authors.forename: Kazuhisa
authors.initials: K
authors.lastname: Yoshifuji
authors.affiliation: Department of Neurosurgery, Kushiro City General Hospital, 1-12 Shunkodai, Kushiro, Hokkaido 085-0822, Japan.
authors.forename: Tatsufumi
authors.initials: T
authors.lastname: Nomura
authors.affiliation: Department of Neurosurgery, Kushiro City General Hospital, 1-12 Shunkodai, Kushiro, Hokkaido 085-0822, Japan.
authors.forename: Katsuya
authors.initials: K
authors.lastname: Komatsu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002533:Cerebral Angiography; D002543:Cerebral Hemorrhage / Q000150:complications* / Q000175:diagnosis; D015331:Cohort Studies; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012008:Recurrence; D012307:Risk Factors; D020521:Stroke / Q000150:complications* / Q000175:diagnosis / Q000453:epidemiology*; D014057:Tomography, X-Ray Computed
keywords: Cerebral microbleeds; intracerebral hemorrhage; recurrence; risk factor; stroke